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4 years ago

Light is not a wave because it does not need a medium

2 answers:

7 0

It's a tough question as to whether light is a wave or a particle..

The statement is FALSE. Not all types of waves need a medium to propagate. Light can travel without a medium.

Extra Information:
Light is a longitudinal wave, sound is transverse.
Longitudinal waves do not need a medium.
Transverse waves need a medium.
This is why, for example, in the vacuum of space, light travels from stars, but sound does not.

ss7ja [257]4 years ago

5 0

the asnwer is false........

You might be interested in

(a) A long, straight solenoid has N turns, uniform cross-sectional area A, and length l. Show that the inductance of this soleno

Paul [167]

Answer:

a. L = μ₀AN²/l b. 1.11 × 10⁻⁷ H

Explanation:

a. The magnetic flux through the solenoid, Ф = NAB where N = number of turns of solenoid, A = cross-sectional area of solenoid and B = magnetic field at center of solenoid = μ₀ni where μ₀ = permeability of free space, n = number of turns per unit length = N/l where l = length of solenoid and i = current in solenoid.

Also, Li = Ф where L = inductance of solenoid.

So, Li = NAB

= NA(μ₀ni)

= NA(μ₀Ni/l)

Li = μ₀AN²i/l

dividing both sides by i, we have

So, L = μ₀AN²/l

b. The self- inductance, L = μ₀AN²/l where

A = πd²/4 where d = diameter of solenoid = 0.150 cm = 1.5 × 10⁻³ m, N = 50 turns, μ₀ = 4π × 10⁻⁷ H/m and l = 5.00 cm = 5 × 10⁻² m

So, L = μ₀AN²/l

L = μ₀πd²N²/4l

L = 4π × 10⁻⁷ H/m × π(1.5 × 10⁻³ m)²(50)²/(4 × 5 × 10⁻² m)

L = 11,103.3 × 10⁻¹¹ H

L = 1.11033 × 10⁻⁷ H

L ≅ 1.11 × 10⁻⁷ H

6 0

3 years ago

A block of weight mg sits on an inclined plane as shown in (Figure 1) . A force of magnitude F1 is applied to pull the block up

svlad2 [7]

Answer:

W = (F1 - mg sin θ) L, W = -μ mg cos θ L

Explanation:

Let's use Newton's second law to find the friction force. In these problems the x axis is taken parallel to the plane and the y axis perpendicular to the plane

Y Axis

N - $W_{y}$ =

N = W_{y}

X axis

F1 - fr - Wₓ = 0

fr = F1 - Wₓ

Let's use trigonometry to find the components of the weight

sin θ = Wₓ / W

cos θ = W_{y} / W

Wₓ = W sin θ

W_{y} = W cos θ

We substitute

fr = F1 - W sin θ

Work is defined by

W = F .dx

W = F dx cos θ

The friction force is parallel to the plane in the negative direction and the displacement is positive along the plane, so the Angle is 180º and the cos θ= -1

W = -fr x

W = (F1 - mg sin θ) L

Another way to calculate is

fr = μ N

fr = μ W cos θ

the work is

W = -μ mg cos θ L

4 0

3 years ago

Which compound should require the highest temperature to melt? LiF, NaF, LiCl, NaCl

Jlenok [28]

Nacl is the answer hahahahaah ha

5 0

3 years ago

Help<br> How much current will flow when a 120 V power supply is connected to a 30<br> resistor ?

AVprozaik [17]

Current= voltage divided by resistance
120/30=4

7 0

3 years ago

. If she

I am Lyosha [343]

Answer:

9 meters

Explanation:

Given:

Mass of Avi is, $m=40\ kg$

Spring constant is, $k=176,400\ N/m$

Compression in the spring is, $x=20\ cm=0.20\ m$

Let the maximum height reached be 'h' m.

Now, as the spring is compressed, there is elastic potential energy stored in the spring. This elastic potential energy is transferred to Avi in the form of gravitational potential energy.

So, by law of conservation of energy, decrease in elastic potential energy is equal to increase in gravitational potential energy.

Decrease in elastic potential energy is given as:

$EPE=\frac{1}{2}kx^2\\EPE=\frac{1}{2}\times 176400\times (0.20)^2\\EPE=88200\times 0.04=3528\ J$

Now, increase in gravitational potential energy is given as:

$GPE=mgh=40\times 9.8\times h=392h$

Now, increase in gravitational potential energy is equal decrease in elastic potential energy. Therefore,

$392h=3528\\\\h=\frac{3528}{392}\\\\h=9\ m$

Therefore, Avi will reach a maximum height of 9 meters.

6 0

3 years ago